AMS 14C ages of post-glacial core sediments from the subaqueous Yangtze delta, along with sedimentary structures and distributions of grain size, pollen spores, and dinoflagellate cysts, show an estuarine depositional system from 13 to 8.4 cal ka BP and a deltaic system from 5.9 cal ka BP to the present. The estuarine system consists of intertidal to subtidal flat, estuarine, and estuarine-front facies, characterized by sand"mud couplets and a high sedimentation rate. The deltaic system includes nearshore shelf and prodelta mud featured by lower sedimentation rate, markedly fewer coastal wetland herbaceous pollens, and more dinoflagellate cysts. We explain the extremely high sedimentation rate during 9.2–8.4 cal ka BP at the study site as a result of rapid sea-level rise, high sediment load due to the unstable monsoonal climate, and subaqueous decrease of elevation from inner to outer estuary. A depositional hiatus occurred during 8.2–5.9 cal ka BP, the transition from estuarine to deltaic system, caused possibly by a shortage of sediment supply resulting from delta initiation in paleo-incised Yangtze valley and strong tidal or storm-related reworking in offshore areas. The subsequent development of deltaic system at the study site indicates accelerated progradation of Yangtze delta post-5.9 cal ka BP.

The Wono and Trego Hot Springs (THS) tephras are widespread in the Lahontan basin and have been identified in a variety of sedimentary environments at different elevations. Davis (1983) reported lake level to be at about 1256 m when the THS tephra was deposited, an interpretation questioned by Benson et al. (1997) who interpreted lake level to be ≤1177 m at that time. This is a significant difference in lake size with important implications for interpreting the climate that prevailed at that time. Based on new interpretations of depositional settings of the THS bed at multiple sites, the larger lake size is correct. Additional sites containing the Wono tephra indicate that it was deposited when lake level was at about 1217 m in the western subbasins and at about 1205 m in the Carson Sink. Sedimentary features associated with progressively deeper paleowater depths follow a predictable pattern that is modulated by proximity to sediment sources and local slope. Fine to coarse sands with wave-formed features are commonly associated with relatively shallow water. Silty clay or clay dominates in paleowater depths >25 m, with thin laminae of sand and ostracods at sites located adjacent to or downslope from steep mountain fronts.

This review analyses the ostracod record in Holocene tsunami deposits, using an overview of the 2004 Indian Ocean tsunami impact on its recent populations and the associated tsunamigenic deposits, together with results from numerous investigations of other Holocene sequences. Different features such as the variability of the local assemblages, population density, species diversity, age population structure (e.g., percentages of adults and juvenile stages) or taphonomical signatures suggest that these microorganisms may be included amongst the most promising tracers of these high-energy events in marshes, lakes, lagoons or shallow marine areas.

Pollen-assemblage data from a sediment core from Hulun Lake in northeastern Inner Mongolia describe the changes in the vegetation and climate of the East Asian monsoon margin during the Holocene. Dry steppe dominated the lake basin from ca. 11,000 to 8000 cal yr BP, suggesting a warm and dry climate. Grasses and birch forests expanded 8000 to 6400 cal yr BP, implying a remarkable increase in the monsoon precipitation. From 6400 to 4400 cal yr BP, the climate became cooler and drier. Chenopodiaceae dominated the interval from 4400 to 3350 cal yr BP, marking extremely dry condition. Artemisia recovered 3350-2050 cal yr BP, denoting an amelioration of climatic conditions. Both temperature and precipitation decreased 2050 to 1000 cal yr BP as indicated by decreased Artemisia and the development of pine forests. During the last 1000 yr, human activities might have had a significant influence on the environment of the lake region. We suggest that the East Asian summer monsoon did not become intensified until 8000 cal yr BP due to the existence of remnant ice sheets in the Northern Hemisphere. Changes in the monsoon precipitation on millennial to centennial scales would be related to ocean-atmosphere interactions in the tropical Pacific.

We have analyzed core MD01-2392, ∽360 km east of the Mekong River mouth in the South China Sea (SCS). Over the past 500 ka, planktonic foraminiferal oxygen-isotopic values are consistently lighter than northern SCS and open-ocean records by up to 0.5‰, indicating the influence of run-off from the Mekong River during both glacial and interglacial periods. Carbonate content is higher during interglacials; sedimentation rates were higher during glacials. Increased sedimentation rates since 30 ka imply increased run-off during the last glacial maximum and Holocene Period. Contrary to general experience, in which it is classed as a warm species for temperature estimates, the thermocline-dwelling species Pulleniatina obliquiloculata increased its numbers during glacial periods. This implies an estuarine circulation and even brackish-water caps during glacial periods, reinforcing the sense of strong run-off. In an overall decline of warm water, the thermocline shoaled stepwise, with rapid rises across the glacial terminations. We infer that the southern SCS was opened to an influx of Indian Ocean waters through southern passages at those times of rising sea levels.

The n-alkane C31/(C29+C31) ratios from surface sediments in the eastern equatorial Pacific (EEP) exhibit higher values to the north and lower values to the south across the southern edge (2–4°N) of the Intertropical Convergence Zone (ITCZ). Since plants tend to synthesize longer chain length n-alkanes in response to elevated temperature and/or aridity, the higher C 31/(C29+C31) ratios at northern sites suggest a higher contribution of vegetation under hot and/or dry conditions. This is consistent with the observation that northern sites receive higher levels of plant waxes transported by northeasterly trade winds from northern South America, where hot and dry conditions prevail. Furthermore, from a sediment core covering the past 750 ka (core HY04; 4°N, 95°W) we found that C31/(C29+C31) ratios exhibit a long-term decrease from MIS (marine oxygen isotope stage) 17 to 13. During this period, the zonal SST (sea-surface temperature) gradient in the equatorial Pacific increased, suggesting an increase in Walker circulation. Such intensified Walker circulation may have enhanced moisture advection from the equatorial Atlantic warm pool to the adjacent northern South America, causing arid regions in northern South America to contract, which may explain long-term decrease in n-alkane chain lengths.

The Diancang Massif is located in a region linking the Tibetan and Yungui Plateaus. Climatically, it is in a transition belt between the south and middle subtropical zones, controlled by Indian monsoon and westerlies. Thus, this study provides more evidences on the evolution of Indian monsoon since the Holocene. We reconstruct the history of climate on the Diancang Massif since 11.5 ka, using integrated correlation of glacial activities, early human settlement sites, and climate proxies abstracted from variations in grain size, magnetic susceptibility, geochemical composition, and pollen in lacustrine sediments. Six climatic stages have been identified. Stage I, from 11.5 ka to 9.0 ka, is a relatively wet period, corresponding to the onset of the Holocene; from 9.5 ka to 6.0 ka, the climate is arid; a cold period follows from 6.0 ka to 5.3 ka, and this is succeeded by a temperate stage from 5.3 ka to 4.0 ka; from 4.0 ka to 0.73 ka the climate is again arid. Compared with other regions dominated by the Indian monsoon, there is a delay in response of the climate on the Diancang Massif to the onset of the Holocene.

Facies analyses of Pleistocene deposits from southern coastal Tanzania (Lindi District) document that sediments formed in a wetland evolving on a coastal terrace in the Lindi Fracture Zone foreland. The exposed succession shows a marked sedimentary change from tidal to terrestrial facies. 14C analyses on gastropod shells indicate the emergence of the Lindi coast at ∼ 44 14C ka BP. Emergence and subsequent elevation of terraces to 21 m above present-day sea level was linked to the falling eustatic sea level prior to the last glacial maximum, and to a periodic elevation due to extensional tectonic episodes in the eastern branch of the East African Rift System (EARS). Since ∼ 44 14C ka BP tectonic uplift at the coast was 80-110 m, comparable to that in the extreme uplift areas of the EARS.

Twenty-two new radiocarbon ages from Skagit valley provide a detailed chronology of alpine glaciation during the Evans Creek stade of the Fraser Glaciation (early marine oxygen isotope stage (MIS) 2) in the Cascade Range, Washington State. Sediments at sites near Concrete, Washington, record two advances of the Baker valley glacier between ca. 30.3 and 19.5 cal ka BP, with an intervening period of glacier recession about 24.9 cal ka BP. The Baker valley glacier dammed lower Skagit valley, creating glacial Lake Concrete, which discharged around the ice dam along Finney Creek, or south into the Sauk valley. Sediments along the shores of Ross Lake in upper Skagit valley accumulated in glacial Lake Skymo after ca. 28.7 cal ka BP behind a glacier flowing out of Big Beaver valley. Horizontally laminated silt and bedded sand and gravel up to 20 m thick record as much as 8000 yr of deposition in these glacially dammed lakes. The data indicate that alpine glaciers in Skagit valley were far less extensive than previously thought. Alpine glaciers remained in advanced positions for much of the Evans Creek stade, which may have ended as early as 20.8 cal ka BP.

Isotopic and cladoceran investigations of Eemian (MIS 5e) lake sediments from Imbramowice, SW Poland, allow us to reconstruct the environmental conditions, especially changes of water level and trophic status, during the early and middle Eemian Interglaciation. We analyzed the sediments from 6.5 to 11.0 m depth in a core provided by Mamakowa (1989). The upper 6.5 m had insufficient carbonates and cladoceran contents for analyses. The analyzed section consists of sandy and organic silts at the bottom, followed by gyttja characterized by increasing CaCO3 content. Measured δ18O values oscillate from ca. -9 to -4‰ and δ13C from -3.5 to above + 6‰. Based on stable isotope analyses of carbonates, we define and characterize eight isotopic horizons (Is). We identify 26 taxa of subfossil Cladocera and seven zones (CLZ) of faunal development. Probably the greatest depth of the lake occurred with pollen zone E2; shallowing then took place. During pollen zones E2-E3, gradual warming is observed and expressed through a positive trend in both δ18O and δ13C values. Pollen zone E4 is characterized by frequent changes of water level. During the Eemian Interglaciation, excluding the initial phase of lake evolution, the lake was meso-eutrophic and eutrophic with high phytoplankton productivity.

The presence of an independently dated marker in an archaeological site offers rare opportunities for assessing the reliability of radiocarbon dates, especially when these are close to the age limit of the technique. Two different pretreatment protocols (routine ABA and more rigorous ABOx-SC) were employed in the chemical preparation of the same charcoal sample from a layer closely associated to the Campanian Ignimbrite tephra at the Russian Palaeolithic site of Kostenki 14 (Markina Gora). The ABA-treated fraction gave an age of ∽33 14C ka BP, comparable to a previous determination from the same layer, whereas the ABOx-SC produced an older age of ∽35 14C ka BP. This is the first radiocarbon determination of an archaeological sample to provide an age consistent with the "calendar" age for the CI tephra marker.

We present a late glacial pollen record (17,700 to 8500 cal yr BP) from a Lake Naleng sediment core. Lake Naleng is located on the southeastern Tibetan Plateau (31.10°N 99.75°E, 4200 m) along the upper tree-line. Variations in the summer monsoon are evident from shifts in vegetation that correspond to late glacial climate trends from other monsoon-sensitive regions. Alpine steppe was recorded between 17,700 and 14,800 cal yr BP, indicating low effective moisture at the study site. Expansion of alpine meadows followed by advances in the position of tree-line around Lake Naleng suggest that climate became warmer and wetter between ∼ 14,800 and 12,500 cal yr BP, probably representing an enhancement of the Asian monsoon. Climatic cooling and reduced effective moisture are inferred from multivariate analysis and the upward retreat of tree-line between ∼ 12,500 and 11,700 cal yr BP. The timing and nature of these shifts to warm, wet and then cold, dry climatic conditions suggest that they correspond to the Bølling/Allerød and Younger Dryas intervals. Abies-Betula forests, representing warm and moist conditions, spread during the early Holocene.

The Whippoorwill Formation is a gleyed diamicton that is present locally within bedrock depressions beneath the oldest glacial till in northern Missouri, USA. Stratigraphy, paleomagnetism, and cosmogenic–nuclide burial ages show that it was deposited between the Matuyama–Gauss magnetostratigraphic boundary at 2.58 Ma and the first advance of the Laurentide ice sheet into Missouri at 2.47 ± 0.19 Ma. High cosmogenic–nuclide concentrations also show that the constituents of the Whippoorwill Formation experienced long exposure at a stable landscape surface with erosion rates of 1–2 m/Ma. However, cosmogenic–nuclide concentrations are invariant with depth below the Whippoorwill Formation surface, indicating active mixing of the soil profile shortly before burial by till. The Whippoorwill Formation retains numerous features indicative of cryoturbation. Therefore, we interpret it as a buried Gelisol, a soil formed under periglacial conditions in the presence of permafrost. At the onset of Northern Hemisphere glaciation, climate cooling established permafrost conditions and accelerated erosion by inducing landscape instability. Thus, weathered regolith materials were mobilized and redeposited by gelifluction shortly before the ice sheet overrode the landscape.

Distal deposits of rhyolitic volcanic ash from the ∼74 ka "supervolcanic" eruption of Toba, in northern Sumatra, are preserved in numerous river valleys across peninsular India. The Toba eruption is hypothesized to have resulted in climate change and the devastation of ecosystems and hominin populations. This study reports the results of the analysis of sediments and stratigraphical sequences from sites in the Jurreru and Middle Son valleys in southern and north-central India. The aim of the study is to determine the extent of palaeoenvironmental change in both valleys as a result of the ash-fall. Inferences based on evidence from the Jurreru valley are more detailed, where pre- and post-Toba palaeoenvironmental changes are divided into seven phases. The results indicate that ash-fall deposits in both valleys underwent several phases of reworking that possibly lasted for several years, indicating that ash was mobile in the landscape for a considerable period of time prior to burial. This could have enhanced and lengthened the detrimental effects of the ash on vegetation and water sources, as well as animal and hominin populations.

The continental margin of southern South Africa exhibits an array of emergent marginal marine sediments permitting the reconstruction of long-term eustatic sea-level changes. We report a suite of optical luminescence ages and supplementary amino acid racemization data, which provide paleosea-level index points for three sites on this coastline. Deposits in the Swartvlei and Groot Brak estuaries display tidal inlet facies overlain by shoreface or eolian facies. Contemporary facies relations suggest a probable high stand 6.0-8.5 m above modern sea level (amsl). At Cape Agulhas, evidence of a past sea-level high stand comprises a gravel beach (ca. 3.8 m amsl) and an overlying sandy shoreface facies (up to 7.5 m amsl). OSL ages between 138±7 ka and 118±7 ka confirm a last interglacial age for all marginal marine facies. The high stand was followed by a sea-level regression that was associated with the accumulation of eolian dunes dating to between 122±7 ka and 113±6 ka. These data provide the first rigorous numerical age constraints for last interglacial sea-level fluctuations in this region, revealing the timing and elevation of the last interglacial high stand to broadly mirror a number of other far-field locations.

The complete paleoecological history from Lake Consuelo forest yields a record of ground-level cloud formation and changes in its lower altitudinal limit over the last 46,300"cal yr BP. The timing of early lake level fluctuations prior to 37,000"cal yr BP appears sensitive to North Atlantic temperature oscillations, corresponding to Dansgaard"Oeschger interstadials 11, 10 and 8 recorded in GISP2. After the LGM, the first hint of warming is recorded in Lake Consuelo at 22,000"cal yr BP and agrees with other estimates for the region. The mid-Holocene (7400"5000"cal yr BP) was the period of highest rates of change and most significant reorganizations in the Consuelo forest. These community changes resulted from a regionally widespread dry period. Results from Lake Consuelo indicate that moisture availability, mediated through cloud cover, played the most significant role in ecological change in this system. Rates of past climate fluctuations never exceeded the forest capacity to accommodate change. Unfortunately, this might not be the case under predicted scenarios for the end of the current century.

The deposits of Glacial Lake Quincy overlie a diamicton associated with the classically defined Illinoian limit in central Indiana. This lake covered at least 180 km2 with a depth of > 20 m and developed when the Illinoian ice sheet retreated 15 km from the maximum limit, causing lake impoundment against Devore Ridge. Overflow from Glacial Lake Quincy eroded across the ridge forming a number of steeped-walled outlets. A section along Mill Creek exposes a sedimentologic sequence associated with Glacial Lake Quincy from a subglacial diamicton to ice-proximal to ice-distal glacial lacustrine sediments. We report new optical ages by multiple aliquot regenerative dose procedure for the fine-grained rhythmically bedded sediments presumed to represent the lowest energy depositional facies, dominated by suspension settling, which maximized sunlight exposure. In turn, optical ages were determined on the fine-grained (4-11 μm) polymineral and quartz fractions under infrared and blue excitation, which yielded statistically similar ages. Optical ages span from ca. 170 to 108 ka, with the average of 16 optical ages indicating deglaciation at ca. 135 ka, generally coincident with Marine Oxygen Isotope Stage 6-to-5 transition and rise in global sea level.

The relationship of sea-level changes and short-term climatic changes with turbidite deposition is poorly documented, although the mechanisms of gravity-driven sediment transport in submarine canyons during sea-level changes have been reported from many regions. This study focuses on the activity of the Dakar Canyon off southern Senegal in response to major glacial/interglacial sea-level shifts and variability in the NW-African continental climate. The sedimentary record from the canyon allows us to determine the timing of turbidite events and on the basis of XRF-scanning element data, we have identified the climate signal at a sub-millennial time scale from the surrounding hemipelagic sediments. Over the late Quaternary the highest frequency in turbidite activity in the Dakar Canyon is confined to major climatic terminations when remobilisation of sediments from the shelf was triggered by the eustatic sea-level rise. However, episodic turbidite events coincide with the timing of Heinrich events in the North Atlantic. During these times continental climate has changed rapidly, with evidence for higher dust supply over NW Africa which has fed turbidity currents. Increased aridity and enhanced wind strength in the southern Saharan–Sahelian zone may have provided a source for this dust.

Deep subpermafrost aquifers are highly climate-dependent, with the permafrost as an aquitard preventing groundwater recharge and discharge. A study from the high-arctic island of Spitsbergen, Svalbard, shows that during a glacial to interglacial phase, both the permafrost and the glacier regime will respond to climatic changes, and a glacier-fed groundwater flow system will vary accordingly. A full glaciation results in the melting of permafrost, and groundwater can flow through pores and fracture systems in the rocks and sediments below the temperate zones of glaciers. These groundwater flow systems will mainly be localized to fjords and valleys and form low-lying terrestrial springs when the relative sea level drops during deglaciation due to glacio-isostatic rise. During an interglaciation, permafrost develops and thickens and the groundwater recharge and discharge areas will thereby be gradually reduced to a minimum reached at the warmest part of an interglaciation. An already frozen spring system cannot reopen before the permafrost melts. Only groundwater springs related to permanently warm-based glacial ice will persist into the next glaciation. During a new glaciation, flow systems that terminated during the previous interglaciation may become revitalized if overridden by warm-based ice causing permafrost thawing.